The present invention relates to an ophthalmologic characteristic measuring apparatus for measuring the shape of the cornea of an eye to be examined, and particularly to an ophthalmologic characteristic measuring apparatus capable of measuring the shape of the cornea precisely in a wide range and more precisely in a narrow range including an important center portion of the cornea.
Conventionally known is an apparatus for measuring the shape of the cornea of an eye to be examined by projecting an index to the cornea and determining a position at which the index is focused.
While the present applicant has developed a technique for measuring the shape of the cornea of an eye to be examined using a wavefront sensor and already filed the patent application thereof, such a technique has a problem that a measuring optical system having a very large aperture must be provided to measure the cornea of the eye in a wide range using the wavefront sensor.
In view of the foregoing, the present invention has been made to provide an ophthalmologic characteristic measuring apparatus capable of more precisely measuring the shape of the more important central portion of the cornea of an eye to be examined using a wavefront sensor; and projecting a plurality of concentric light beams to the peripheral portion of the cornea of the eye, receiving the reflected light rays, and determining the shape of the peripheral portion of the cornea on the basis of the light receiving positions.